1. Field of the Invention
The present invention relates to a flushing device in the bathroom, particularly to a button-controlled pressure flushing device.
2. Description of the Related Art
Basically, there are three kinds of existing flushing devices, one is to hang the water tank aloft. The high hanging water tank converts a high potential energy of the water into the kinetic energy of the same to flush filthy substances in the toilet. However, afore flushing means substantially wastes the treasure water resource. An other of the flushing devices enlarges the diameter of an outlet pipe to swiftly wash out the filthy substances in the toilet. Nonetheless, the larger diameter readily results in dripping, and the treasure water is also adversely wasted. The other of the flushing devices is directed to a pressure flushing device including a sealed water tank, a flushing valve, a flushing switch, and a one-way valve. Wherein, the sealed water tank installs an inlet, the flushing valve is densely disposed on the bottom of the sealed water tank, and a running water pipe connects to the inlet of the sealed water tank via the one-way valve. As a result, when the sealed water tank is filled with water, the soaring water level would compress the air therein, so that the water becomes the high-pressure water. Since the atmospheric pressure is as same as the hydraulic pressure in the running water pipe, the soaring water level of the running water would thence provide a stored pressure, and the sealed water tank could thence store water to compress the air therein. Wherein, this flushing means with high-pressure water to provide a jet stream is generally acknowledged as the most efficient way to save water. A pressure flushing device for the squatting toilet disclosed by the CN Patent Number 200420060321.2 issued the combination of a tank body, a valve body, an air induce member, an outlet member, a flushing member, and an air-water mixture device. Wherein, this flushing device further includes a case and an anti-backflow device. In addition, the case is installed on the tank body, and a decorative cover connects to the tank body. Moreover, the anti-backflow device has a protective casing for backflow prevention, a pressure maintaining piston, a spring, and a core part. Herein, the protective casing for backflow prevention is fixed to the inlet valve body, and the core part with a ball is disposed inside the protective casing. The pressure maintaining piston provides with a pressure maintaining ball and a sealing member, which is pressed in the inlet valve body via the spring. Further, the air induce device includes an air induce core and an air induce nut; whereby, the air induce core would be mounted on the inlet valve body via the air induce nut. The outlet device consists of an inner screw shaft, an outer screw shaft, a spring, a valve needle, a spiral wall, a sleeve, and a plug. After the inner screw shaft surrounded by the spring and the sealing member penetrates through the outer screw shaft for mounting on a smaller plug; the valve needle would be thence installed in the needle base, and the needle base would be installed inside the outlet valve body. The outer screw shaft further goes through the spring and the sealing member so as to get through the sleeve and install in the plug. Moreover, the sleeve is fixed inside the valve body, and the sleeve has the sealing member disposed thereon. The flushing device includes a flush piston rod, a spring, a plug head, and a flush piston. Wherein, the flush piston rod has the spring installed on an inner side thereof, a sealing member is installed on the joint of the flush piston rod, the plug head is further disposed on the spring, and the flush piston engages with the threads on the flush piston rod. Thereby the entire flushing device would be embedded in an upper case for suiting to a weephole of a lower case. Nevertheless, the abovementioned disclosure has the disadvantages of the complicated parts and structure as well as the high cost and non-reliability. Especially, the above disclosure has to be executed with a long time. Moreover, although the hydraulic pressure is high during flushing, the flow is still not large enough for achieving an efficient flushing. In addition, the volume of water is fixed, so users are unable to adjust the volume according to the practical condition. Thus, the aforesaid means is still incapable of achieving the preferred water-saving efficiency, which is adverse to promote the product.